Touch-sensitive system with motion filtering

ABSTRACT

A stylus includes a pen-tip; a sensor; and a processor operable to: operate in a lower-power mode and a higher-power mode; detect, with the sensor, a defined frequency or a defined range of frequencies indicating shaking of the stylus; and transition from the lower-power mode to the higher-power mode in response to the detection of the defined frequency or the defined range of frequencies. The processor is prevented from transitioning from the lower-power mode to the higher-power mode in response to detection of a frequency other than the defined frequency and a range of frequencies other than the defined range of frequencies. The processor, in response to a relative motion between the stylus and a device in communication with the stylus, process both a device signal representative of the relative motion and a stylus signal representative of the detection of the defined frequency or the defined range of frequencies.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority of U.S. application Ser. No.16/579,525, filed Sep. 23, 2019, which claims the benefit, under 35U.S.C. §119(e), of U.S. Provisional Patent Application No. 61/553114,filed 28 Oct. 2011, which is incorporated herein by reference.

BACKGROUND Technical Field

This disclosure generally relates to touch-sensitive systems.

Description of the Related Art

A touch sensor may detect the presence and location of a touch or theproximity of an object (such as a user's finger or a stylus) within atouch-sensitive area of the touch sensor overlaid on a display screen,for example. In a touch-sensitive-display application, the touch sensormay enable a user to interact directly with what is displayed on thescreen, rather than indirectly with a mouse or touch pad. A touch sensormay be attached to or provided as part of a desktop computer, laptopcomputer, tablet computer, personal digital assistant (PDA), smartphone,satellite navigation device, portable media player, portable gameconsole, kiosk computer, point-of-sale device, or other suitable device.A control panel on a household or other appliance may include a touchsensor.

There are a number of different types of touch sensors, such as, forexample, resistive touch screens, surface acoustic wave touch screens,and capacitive touch screens. Herein, reference to a touch sensor mayencompass a touch screen, and vice versa, where appropriate. When anobject touches or comes within proximity of the surface of thecapacitive touch screen, a change in capacitance may occur within thetouch screen at the location of the touch or proximity. A touch-sensorcontroller may process the change in capacitance to determine itsposition on the touch screen.

Brief Summary

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 illustrates an example touch sensor with an example touch-sensorcontroller.

FIG. 2 illustrates an example active stylus exterior.

FIG. 3 illustrates an example active stylus interior.

FIG. 4 illustrates an example active stylus with touch sensor device.

FIG. 5 illustrates an example method for determining whether motion of astylus or device is unintentional and processing signals generated bythe motion to correct for unintended motion.

DETAILED DESCRIPTION

FIG. 1 illustrates an example touch sensor 10 with an exampletouch-sensor controller 12. Touch sensor 10 and touch-sensor controller12 may detect the presence and location of a touch or the proximity ofan object within a touch-sensitive area of touch sensor 10. Herein,reference to a touch sensor may encompass both the touch sensor and itstouch-sensor controller, where appropriate. Similarly, reference to atouch-sensor controller may encompass both the touch-sensor controllerand its touch sensor, where appropriate. Touch sensor 10 may include oneor more touch-sensitive areas, where appropriate. Touch sensor 10 mayinclude an array of drive and sense electrodes (or an array ofelectrodes of a single type) disposed on one or more substrates, whichmay be made of a dielectric material. Herein, reference to a touchsensor may encompass both the electrodes of the touch sensor and thesubstrate(s) that they are disposed on, where appropriate.Alternatively, where appropriate, reference to a touch sensor mayencompass the electrodes of the touch sensor, but not the substrate(s)that they are disposed on

An electrode (whether a ground electrode, guard electrode, driveelectrode, or sense electrode) may be an area of conductive materialforming a shape, such as for example a disc, square, rectangle, thinline, other suitable shape, or suitable combination of these. One ormore cuts in one or more layers of conductive material may (at least inpart) create the shape of an electrode, and the area of the shape may(at least in part) be bounded by those cuts. In particular embodiments,the conductive material of an electrode may occupy approximately 100% ofthe area of its shape. As an example and not by way of limitation, anelectrode may be made of indium tin oxide (ITO) and the ITO of theelectrode may occupy approximately 100% of the area of its shape(sometimes referred to as a 100% fill), where appropriate. In particularembodiments, the conductive material of an electrode may occupysubstantially less than 100% of the area of its shape. As an example,and not by way of limitation, an electrode may be made of fine lines ofmetal or other conductive material (FLM), such as for example copper,silver, or a copper- or silver-based material, and the fine lines ofconductive material may occupy approximately 5% of the area of its shapein a hatched, mesh, or other suitable pattern. Herein, reference to FLMencompasses such material, where appropriate. Although this disclosuredescribes or illustrates particular electrodes made of particularconductive material forming particular shapes with particular fillpercentages having particular patterns, this disclosure contemplates anysuitable electrodes made of any suitable conductive material forming anysuitable shapes with any suitable fill percentages having any suitablepatterns.

Where appropriate, the shapes of the electrodes (or other elements) of atouch sensor may constitute in whole or in part one or moremacro-features of the touch sensor. One or more characteristics of theimplementation of those shapes (such as, for example, the conductivematerials, fills, or patterns within the shapes) may constitute in wholeor in part one or more micro-features of the touch sensor. One or moremacro-features of a touch sensor may determine one or morecharacteristics of its functionality, and one or more micro-features ofthe touch sensor may determine one or more optical features of the touchsensor, such as transmittance, refraction, or reflection.

A mechanical stack may contain the substrate (or multiple substrates)and the conductive material forming the drive or sense electrodes oftouch sensor 10. As an example and not by way of limitation, themechanical stack may include a first layer of optically clear adhesive(OCA) beneath a cover panel. The cover panel may be clear and made of aresilient material suitable for repeated touching, such as for exampleglass, polycarbonate, or poly(methyl methacrylate) (PMMA). Thisdisclosure contemplates any suitable cover panel made of any suitablematerial. The first layer of OCA may be disposed between the cover paneland the substrate with the conductive material forming the drive orsense electrodes. The mechanical stack may also include a second layerof OCA and a dielectric layer (which may be made of PET or anothersuitable material, similar to the substrate with the conductive materialforming the drive or sense electrodes). As an alternative, whereappropriate, a thin coating of a dielectric material may be appliedinstead of the second layer of OCA and the dielectric layer. The secondlayer of OCA may be disposed between the substrate with the conductivematerial making up the drive or sense electrodes and the dielectriclayer, and the dielectric layer may be disposed between the second layerof OCA and an air gap to a display of a device including touch sensor 10and touch-sensor controller 12. As an example only and not by way oflimitation, the cover panel may have a thickness of approximately 1 mm;the first layer of OCA may have a thickness of approximately 0.05 mm;the substrate with the conductive material forming the drive or senseelectrodes may have a thickness of approximately 0.05 mm; the secondlayer of OCA may have a thickness of approximately 0.05 mm; and thedielectric layer may have a thickness of approximately 0.05 mm. Althoughthis disclosure describes a particular mechanical stack with aparticular number of particular layers made of particular materials andhaving particular thicknesses, this disclosure contemplates any suitablemechanical stack with any suitable number of any suitable layers made ofany suitable materials and having any suitable thicknesses. As anexample and not by way of limitation, in particular embodiments, a layerof adhesive or dielectric may replace the dielectric layer, second layerof OCA, and air gap described above, with there being no air gap to thedisplay.

One or more portions of the substrate of touch sensor 10 may be made ofpolyethylene terephthalate (PET) or another suitable material. Thisdisclosure contemplates any suitable substrate with any suitableportions made of any suitable material. In particular embodiments, thedrive or sense electrodes in touch sensor 10 may be made of ITO in wholeor in part. In particular embodiments, the drive or sense electrodes intouch sensor 10 may be made of fine lines of metal or other conductivematerial. As an example and not by way of limitation, one or moreportions of the conductive material may be copper or copper-based andhave a thickness of approximately 5 μm or less and a width ofapproximately 10 μm or less. As another example, one or more portions ofthe conductive material may be silver or silver-based and similarly havea thickness of approximately 5μm or less and a width of approximately 10μm or less. This disclosure contemplates any suitable electrodes made ofany suitable material.

Touch sensor 10 may implement a capacitive form of touch sensing. In amutual-capacitance implementation, touch sensor 10 may include an arrayof drive and sense electrodes forming an array of capacitive nodes. Adrive electrode and a sense electrode may form a capacitive node. Thedrive and sense electrodes forming the capacitive node may come neareach other, but not make electrical contact with each other. Instead,the drive and sense electrodes may be capacitively coupled to each otheracross a space between them. A pulsed or alternating voltage applied tothe drive electrode (by touch-sensor controller 12) may induce a chargeon the sense electrode, and the amount of charge induced may besusceptible to external influence (such as a touch or the proximity ofan object). When an object touches or comes within proximity of thecapacitive node, a change in capacitance may occur at the capacitivenode and touch-sensor controller 12 may measure the change incapacitance. By measuring changes in capacitance throughout the array,touch-sensor controller 12 may determine the position of the touch orproximity within the touch-sensitive area(s) of touch sensor 10.

In a self-capacitance implementation, touch sensor 10 may include anarray of electrodes of a single type that may each form a capacitivenode. When an object touches or comes within proximity of the capacitivenode, a change in self-capacitance may occur at the capacitive node andcontroller 12 may measure the change in capacitance, for example, as achange in the amount of charge needed to raise the voltage at thecapacitive node by a pre-determined amount. As with a mutual-capacitanceimplementation, by measuring changes in capacitance throughout thearray, controller 12 may determine the position of the touch orproximity within the touch-sensitive area(s) of touch sensor 10. Thisdisclosure contemplates any suitable form of capacitive touch sensing,where appropriate.

In particular embodiments, one or more drive electrodes may togetherform a drive line running horizontally or vertically or in any suitableorientation. Similarly, one or more sense electrodes may together form asense line running horizontally or vertically or in any suitableorientation. In particular embodiments, drive lines may runsubstantially perpendicular to sense lines. Herein, reference to a driveline may encompass one or more drive electrodes making up the driveline, and vice versa, where appropriate. Similarly, reference to a senseline may encompass one or more sense electrodes making up the senseline, and vice versa, where appropriate.

Touch sensor 10 may have drive and sense electrodes disposed in apattern on one side of a single substrate. In such a configuration, apair of drive and sense electrodes capacitively coupled to each otheracross a space between them may form a capacitive node. For aself-capacitance implementation, electrodes of only a single type may bedisposed in a pattern on a single substrate. In addition or as analternative to having drive and sense electrodes disposed in a patternon one side of a single substrate, touch sensor 10 may have driveelectrodes disposed in a pattern on one side of a substrate and senseelectrodes disposed in a pattern on another side of the substrate.Moreover, touch sensor 10 may have drive electrodes disposed in apattern on one side of one substrate and sense electrodes disposed in apattern on one side of another substrate. In such configurations, anintersection of a drive electrode and a sense electrode may form acapacitive node. Such an intersection may be a location where the driveelectrode and the sense electrode “cross” or come nearest each other intheir respective planes. The drive and sense electrodes do not makeelectrical contact with each other—instead they are capacitively coupledto each other across a dielectric at the intersection. Although thisdisclosure describes particular configurations of particular electrodesforming particular nodes, this disclosure contemplates any suitableconfiguration of any suitable electrodes forming any suitable nodes.Moreover, this disclosure contemplates any suitable electrodes disposedon any suitable number of any suitable substrates in any suitablepatterns.

As described above, a change in capacitance at a capacitive node oftouch sensor 10 may indicate a touch or proximity input at the positionof the capacitive node. Touch-sensor controller 12 may detect andprocess the change in capacitance to determine the presence and locationof the touch or proximity input. Touch-sensor controller 12 may thencommunicate information about the touch or proximity input to one ormore other components (such one or more central processing units (CPUs))of a device that includes touch sensor 10 and touch-sensor controller12, which may respond to the touch or proximity input by initiating afunction of the device (or an application running on the device).Although this disclosure describes a particular touch-sensor controllerhaving particular functionality with respect to a particular device anda particular touch sensor, this disclosure contemplates any suitabletouch-sensor controller having any suitable functionality with respectto any suitable device and any suitable touch sensor.

Touch-sensor controller 12 may be one or more integrated circuits (ICs),such as for example general-purpose microprocessors, microcontrollers,programmable logic devices (PLDs) or programmable logic arrays (PLAs),application-specific ICs (ASICs). In particular embodiments,touch-sensor controller 12 comprises analog circuitry, digital logic,and digital non-volatile memory. In particular embodiments, touch-sensorcontroller 12 is disposed on a flexible printed circuit (FPC) bonded tothe substrate of touch sensor 10, as described below. The FPC may beactive or passive, where appropriate. In particular embodiments multipletouch-sensor controllers 12 are disposed on the FPC. Touch-sensorcontroller 12 may include a processor unit, a drive unit, a sense unit,and a storage unit. The drive unit may supply drive signals to the driveelectrodes of touch sensor 10. The sense unit may sense charge at thecapacitive nodes of touch sensor 10 and provide measurement signals tothe processor unit representing capacitances at the capacitive nodes.The processor unit may control the supply of drive signals to the driveelectrodes by the drive unit and process measurement signals from thesense unit to detect and process the presence and location of a touch orproximity input within the touch-sensitive area(s) of touch sensor 10.The processor unit may also track changes in the position of a touch orproximity input within the touch-sensitive area(s) of touch sensor 10.The storage unit may store programming for execution by the processorunit, including programming for controlling the drive unit to supplydrive signals to the drive electrodes, programming for processingmeasurement signals from the sense unit, and other suitable programming,where appropriate. Although this disclosure describes a particulartouch-sensor controller having a particular implementation withparticular components, this disclosure contemplates any suitabletouch-sensor controller having any suitable implementation with anysuitable components.

Tracks 14 of conductive material disposed on the substrate of touchsensor 10 may couple the drive or sense electrodes of touch sensor 10 toconnection pads 16, also disposed on the substrate of touch sensor 10.As described below, connection pads 16 facilitate coupling of tracks 14to touch-sensor controller 12. Tracks 14 may extend into or around(e.g., at the edges of) the touch-sensitive area(s) of touch sensor 10.Particular tracks 14 may provide drive connections for couplingtouch-sensor controller 12 to drive electrodes of touch sensor 10,through which the drive unit of touch-sensor controller 12 may supplydrive signals to the drive electrodes. Other tracks 14 may provide senseconnections for coupling touch-sensor controller 12 to sense electrodesof touch sensor 10, through which the sense unit of touch-sensorcontroller 12 may sense charge at the capacitive nodes of touch sensor10. Tracks 14 may be made of fine lines of metal or other conductivematerial. As an example and not by way of limitation, the conductivematerial of tracks 14 may be copper or copper-based and have a width ofapproximately 100 μm or less. As another example, the conductivematerial of tracks 14 may be silver or silver-based and have a width ofapproximately 100 μm or less. In particular embodiments, tracks 14 maybe made of ITO in whole or in part in addition or as an alternative tofine lines of metal or other conductive material. Although thisdisclosure describes particular tracks made of particular materials withparticular widths, this disclosure contemplates any suitable tracks madeof any suitable materials with any suitable widths. In addition totracks 14, touch sensor 10 may include one or more ground linesterminating at a ground connector (which may be a connection pad 16) atan edge of the substrate of touch sensor 10 (similar to tracks 14).

Connection pads 16 may be located along one or more edges of thesubstrate, outside the touch-sensitive area(s) of touch sensor 10. Asdescribed above, touch-sensor controller 12 may be on an FPC. Connectionpads 16 may be made of the same material as tracks 14 and may be bondedto the FPC using an anisotropic conductive film (ACF). Connection 18 mayinclude conductive lines on the FPC coupling touch-sensor controller 12to connection pads 16, in turn coupling touch-sensor controller 12 totracks 14 and to the drive or sense electrodes of touch sensor 10. Inanother embodiment, connection pads 16 may be connected to anelectro-mechanical connector (such as a zero insertion forcewire-to-board connector); in this embodiment, connection 18 may not needto include an FPC. This disclosure contemplates any suitable connection18 between touch-sensor controller 12 and touch sensor 10.

FIG. 2 illustrates an example exterior of an example active stylus 20.Active stylus 20 may include one or more components, such as buttons 30or sliders 32 and 34 integrated with an outer body 22. These externalcomponents may provide for interaction between active stylus 20 and auser or between a device and a user. As an example and not by way oflimitation, interactions may include communication between active stylus20 and a device, enabling or altering functionality of active stylus 20or a device, or providing feedback to or accepting input from one ormore users. The device may by any suitable device, such as, for exampleand without limitation, a desktop computer, laptop computer, tabletcomputer, personal digital assistant (PDA), smartphone, satellitenavigation device, portable media player, portable game console, kioskcomputer, point-of-sale device, or other suitable device. Although thisdisclosure provides specific examples of particular componentsconfigured to provide particular interactions, this disclosurecontemplates any suitable component configured to provide any suitableinteraction. Active stylus 20 may have any suitable dimensions withouter body 22 made of any suitable material or combination of materials,such as, for example and without limitation, plastic or metal. Inparticular embodiments, exterior components (e.g., 30 or 32) of activestylus 20 may interact with internal components or programming of activestylus 20 or may initiate one or more interactions with one or moredevices or other active styluses 20.

As described above, actuating one or more particular components mayinitiate an interaction between active stylus 20 and a user or betweenthe device and the user. Components of active stylus 20 may include oneor more buttons 30 or one or more sliders 32 and 34. As an example andnot by way of limitation, buttons 30 or sliders 32 and 34 may bemechanical or capacitive and may function as a roller, trackball, orwheel. As another example, one or more sliders 32 or 34 may function asa vertical slider 34 aligned along a longitudinal axis, while one ormore wheel sliders 32 may be aligned along the circumference of activestylus 20. In particular embodiments, capacitive sliders 32 and 34 orbuttons 30 may be implemented using one or more touch-sensitive areas.Touch-sensitive areas may have any suitable shape, dimensions, location,or be made from any suitable material. As an example and not by way oflimitation, sliders 32 and 34 or buttons 30 may be implemented usingareas of flexible mesh formed using lines of conductive material. Asanother example, sliders 32 and 34 or buttons 30 may be implementedusing a FPC.

Active stylus 20 may have one or more components configured to providefeedback to or accepting feedback from a user, such as, for example andwithout limitation, tactile, visual, or audio feedback. Active stylus 20may include one or more ridges or grooves 24 on its outer body 22.Ridges or grooves 24 may have any suitable dimensions, have any suitablespacing between ridges or grooves, or be located at any suitable area onouter body 22 of active stylus 20. As an example and not by way oflimitation, ridges 24 may enhance a user's grip on outer body 22 ofactive stylus 20 or provide tactile feedback to or accept tactile inputfrom a user. Active stylus 20 may include one or more audio components38 capable of transmitting and receiving audio signals. As an exampleand not by way of limitation, audio component 38 may contain amicrophone capable of recording or transmitting one or more users'voices. As another example, audio component 38 may provide an auditoryindication of a power status of active stylus 20. Active stylus 20 mayinclude one or more visual feedback components 36, such as alight-emitting diode (LED) indicator. As an example and not by way oflimitation, visual feedback component 36 may indicate a power status ofactive stylus 20 to the user.

One or more modified surface areas 40 may form one or more components onouter body 22 of active stylus 20. Properties of modified surface areas40 may be different than properties of the remaining surface of outerbody 22. As an example and not by way of limitation, modified surfacearea 40 may be modified to have a different texture, temperature, orelectromagnetic characteristic relative to the surface properties of theremainder of outer body 22. Modified surface area 40 may be capable ofdynamically altering its properties, for example by using hapticinterfaces or rendering techniques. A user may interact with modifiedsurface area 40 to provide any suitable functionally. For example andnot by way of limitation, dragging a finger across modified surface area40 may initiate an interaction, such as data transfer, between activestylus 20 and a device.

One or more components of active stylus 20 may be configured tocommunicate data between active stylus 20 and the device. For example,active stylus 20 may include one or more tips 26 or nibs. Tip 26 mayinclude one or more electrodes configured to communicate data betweenactive stylus 20 and one or more devices or other active styluses. Tip26 may be made of any suitable material, such as a conductive material,and have any suitable dimensions, such as, for example, a diameter of 1mm or less at its terminal end. Active stylus 20 may include one or moreports 28 located at any suitable location on outer body 22 of activestylus 20. Port 28 may be configured to transfer signals or informationbetween active stylus 20 and one or more devices or power sources. Port28 may transfer signals or information by any suitable technology, suchas, for example, by universal serial bus (USB) or Ethernet connections.Although this disclosure describes and illustrates a particularconfiguration of particular components with particular locations,dimensions, composition and functionality, this disclosure contemplatesany suitable configuration of suitable components with any suitablelocations, dimensions, composition, and functionality with respect toactive stylus 20.

FIG. 3 illustrates an example internal components of example activestylus 20. Active stylus 20 may include one or more internal components,such as a controller 50, sensors 42, memory 44, or power source 48. Inparticular embodiments, one or more internal components may beconfigured to provide for interaction between active stylus 20 and auser or between a device and a user. In other particular embodiments,one or more internal components, in conjunction with one or moreexternal components described above, may be configured to provideinteraction between active stylus 20 and a user or between a device anda user. As an example and not by way of limitation, interactions mayinclude communication between active stylus 20 and a device, enabling oraltering functionality of active stylus 20 or a device, or providingfeedback to or accepting input from one or more users.

Controller 50 may be a microcontroller or any other type of processorsuitable for controlling the operation of active stylus 20. Controller50 may be one or more ICs—such as, for example, general-purposemicroprocessors, microcontrollers, PLDs, PLAs, or ASICs. Controller 50may include a processor unit, a drive unit, a sense unit, and a storageunit. The drive unit may supply signals to electrodes of tip 26 throughcenter shaft 41. The drive unit may also supply signals to control ordrive sensors 42 or one or more external components of active stylus 20.The sense unit may sense signals received by electrodes of tip 26through center shaft 41 and provide measurement signals to the processorunit representing input from a device. The sense unit may also sensesignals generated by sensors 42 or one or more external components andprovide measurement signals to the processor unit representing inputfrom a user. The processor unit may control the supply of signals to theelectrodes of tip 26 and process measurement signals from the sense unitto detect and process input from the device. The processor unit may alsoprocess measurement signals from sensors 42 or one or more externalcomponents. The storage unit may store programming for execution by theprocessor unit, including programming for controlling the drive unit tosupply signals to the electrodes of tip 26, programming for processingmeasurement signals from the sense unit corresponding to input from thedevice, programming for processing measurement signals from sensors 42or external components to initiate a pre-determined function or gestureto be performed by active stylus 20 or the device, and other suitableprogramming, where appropriate. As an example and not by way oflimitation, programming executed by controller 50 may electronicallyfilter signals received from the sense unit. Although this disclosuredescribes a particular controller 50 having a particular implementationwith particular components, this disclosure contemplates any suitablecontroller having any suitable implementation with any suitablecomponents.

In particular embodiments, active stylus 20 may include one or moresensors 42, such as touch sensors, gyroscopes, accelerometers, contactsensors, or any other type of sensor that detect or measure data aboutthe environment in which active stylus 20 operates. Sensors 42 maydetect and measure one or more characteristic of active stylus 20, suchas acceleration or movement, orientation, contact, pressure on outerbody 22, force on tip 26, vibration, or any other suitablecharacteristic of active stylus 20. As an example and not by way oflimitation, sensors 42 may be implemented mechanically, electronically,or capacitively. As described above, data detected or measured bysensors 42 communicated to controller 50 may initiate a pre-determinedfunction or gesture to be performed by active stylus 20 or the device.In particular embodiments, data detected or received by sensors 42 maybe stored in memory 44. Memory 44 may be any form of memory suitable forstoring data in active stylus 20. In other particular embodiments,controller 50 may access data stored in memory 44. As an example and notby way of limitation, memory 44 may store programming for execution bythe processor unit of controller 50. As another example, data measuredby sensors 42 may be processed by controller 50 and stored in memory 44.

Power source 48 may be any type of stored-energy source, includingelectrical or chemical-energy sources, suitable for powering theoperation of active stylus 20. In particular embodiments, power source48 may be charged by energy from a user or device. As an example and notby way of limitation, power source 48 may be a rechargeable battery thatmay be charged by motion induced on active stylus 20. In otherparticular embodiments, power source 48 of active stylus 20 may providepower to or receive power from the device. As an example and not by wayof limitation, power may be inductively transferred between power source48 and a power source of the device.

FIG. 4 illustrates an example active stylus 20 with an example device52. Device 52 may have a display (not shown) and a touch sensor with atouch-sensitive area 54. Device 52 display may be a liquid crystaldisplay (LCD), a LED display, a LED-backlight LCD, or other suitabledisplay and may be visible though a cover panel and substrate (and thedrive and sense electrodes of the touch sensor disposed on it) of device52. Although this disclosure describes a particular device display andparticular display types, this disclosure contemplates any suitabledevice display and any suitable display types.

Device 52 electronics may provide the functionality of device 52. Asexample and not by way of limitation, device 52 electronics may includecircuitry or other electronics for wireless communication to or fromdevice 52, execute programming on device 52, generating graphical orother user interfaces (UIs) for device 52 display to display to a user,managing power to device 52 from a battery or other power source, takingstill pictures, recording video, other suitable functionality, or anysuitable combination of these. Although this disclosure describesparticular device electronics providing particular functionality of aparticular device, this disclosure contemplates any suitable deviceelectronics providing any suitable functionality of any suitable device.

In particular embodiments, active stylus 20 and device 52 may besynchronized prior to communication of data between active stylus 20 anddevice 52. As an example and not by way of limitation, active stylus 20may be synchronized to device 52 through a pre-determined modulationscheme and/or bit sequence transmitted by the touch sensor of device 52.As another example, active stylus 20 may be synchronized to device byprocessing the drive signal transmitted by drive electrodes of the touchsensor of device 52. Active stylus 20 may interact or communicate withdevice 52 when active stylus 20 is brought in contact with or inproximity to touch-sensitive area 54 of the touch sensor of device 52.In particular embodiments, interaction between active stylus 20 anddevice 52 may be capacitive or inductive. As an example and not by wayof limitation, when active stylus 20 is brought in contact with or inthe proximity of touch-sensitive area 54 of device 52, signals generatedby active stylus 20 may influence capacitive nodes of touch-sensitivearea of device 52 or vice versa. As another example, a power source ofactive stylus 20 may be inductively charged through the touch sensor ofdevice 52, or vice versa. Although this disclosure describes particularinteractions and communications between active stylus 20 and device 52,this disclosure contemplates any suitable interactions andcommunications through any suitable means, such as mechanical forces,current, voltage, or electromagnetic fields.

In particular embodiments, measurement signal from the sensors of activestylus 20 may initiate, provide for, or terminate interactions betweenactive stylus 20 and one or more devices 52 or one or more users, asdescribed above. Interaction between active stylus 20 and device 52 mayoccur when active stylus 20 is contacting or in the proximity of device52. As an example and not by way of limitation, interactions may includeor be initiated by gestures such as shaking or inverting active stylus20 on or near device 52, pressure placed on the tip of active stylus 20,or pressure placed on the body of active stylus 20 (for example, from auser's grip on the stylus). Active stylus may interact with device 52based on the gesture performed with active stylus 20 to initiate apre-determined function, such as authenticating a user associated withactive stylus 20 or device 52. Although this disclosure describesparticular movements providing particular types of interactions betweenactive stylus 20 and device 52, this disclosure contemplates anysuitable movement influencing any suitable interaction in any suitableway.

In particular embodiments, motion of a stylus or a device may beassociated with particular functionality. As an example, moving thestylus near a touch-sensitive element of the device may add to edit, ordelete content displayed on the device. As another example, executing anauthentication gesture with a stylus may provide access to data,content, menus, or settings associated with a user, stylus, device, orprograms on the stylus or device. Motions and associated functions arenot limited to the examples above, and this disclosure contemplates anysuitable motion of a stylus or device associated with any suitablefunctionality. Moreover, although this disclosure describes orillustrates motion of a stylus, particular embodiments encompass motionof a person's finger or another object, such as a passive stylus orother suitable conductive object. Herein, particular embodimentsdescribed or illustrated as involving a stylus may, where appropriate,similarly involve a person's finger or another object other than astylus. In addition, the descriptions and examples of this disclosurecontemplate any suitable stylus, for example and not by way oflimitation a passive or an active stylus.

Some of the motion of the stylus or the device may not be intended by auser, resulting in unintended functionality. “Unintended motion” mayrefer to motion in any dimension of a stylus, a device, or both relativeto each other or relative to a fixed point. In particular embodiments,motion may be characterized as unintended, triggering functionality orpreventing associated functionality from occurring, such as activationof components that consume large amounts of power. FIG. 5 represents anexample method for determining whether motion of a stylus or a device isunintentional and correcting for the unintended motion. The method ofFIG. 5 begins at step 56, where motion of a stylus, a device, or bothoccurs. At step 58, the motion of the stylus or the device produces oneor more signals based on the motion, for example signals generated by anaccelerometer, gyroscope, magnetometer, global positioning system (GPS),charge present in a touch-sensitive element of the device, or anysuitable transducer. The signal may undergo any suitable processing ormodification at any suitable stage or time from the signal's creation toits intended use, such as conveying information or providingfunctionality. In step 60, at any suitable stage from its creation toits intended use the signal, any portion of the signal, the signal'scharacteristics, or any suitable combination thereof is compared to oneor more motion profiles 62. Motion profiles 62 define unintended motionby identifying particular signals, portions of signals, orcharacteristics of signals representing or relating to motion of astylus, a device, or both. The signals or portions of signals identifiedmay relate to signals at any suitable stage or time from the signal'screation to its intended use. As an example, signals identified bymotion profile 62 may be based on the acceleration of the motion, theduration of the motion, the location or orientation of the stylus ordevice before, during or after the motion occurs, one or more temporalfrequencies comprising the motion, a pre-defined motion or sequence ofmotions, the type of motion performed (such as rotation or translation),or any other suitable characteristic, type, or sequence of motions. Asan example, signals identified by motion profiles 62 may include one ormore frequencies or ranges of frequencies that indicate unwanted motion,such as shaking of the stylus created by involuntary shaking of the useror frequencies generated by walking with the stylus in a pocket. Asanother example, signals identified by motion profiles 62 may includeinformation about the acceleration of the motion, such as sudden,extreme motion relative to normal acceleration during normal operation.As another example, signals identified by motion profiles 62 maycomprise a sequence of motions of the stylus, such as particularrotations or repetitive motions that occur when a user is moving thestylus merely to move the stylus, not to access or initiate anyfunctionality associated with the stylus or device. For instance, a userwho absent-mindedly twirls a writing instrument may twirl the stylus inthe same way, and signals representing this motion would be stored inmotion profiles 62 and filtered. As another example, signals identifiedby motion profiles 62 may include information about the orientation of astylus or device and their relative positions. For example, movementoccurring when the stylus is nowhere near the device may be designatedas unintended. As another example, a motion profile may identify one ormore frequencies or ranges of frequencies, amplitudes or ranges ofamplitudes, or other suitable characteristics or ranges ofcharacteristics to filter from the signals. While the above examplesreference movements of a stylus, signals identified by motion profiles62 may also indicated unwanted movement of a device as well. Moreover,while this disclosure provides specific examples of types orcharacteristics of motion that may be described as unintended by amotion profile, this disclosure contemplates a motion profile describingany suitable motion, sequence of motions, or characteristics of motion.

In particular embodiments, motion profile 62 may be defined at least inpart by a user of the stylus or the device, for example through agraphical user interface. Motion profile 62 may also be defined by thestylus or the device. As an example, a user may tag certain motions asunintended, for example by clicking a button on a stylus after a motionhas been performed. The stylus or device records the tagged motion inmotion profile 62, and over time may refine motion profile 62 byanalyzing a set of characteristics common or frequently appearing inmotion marked as unintended. As another example, the stylus or devicemay have a testing period in which the user performs a particularfunction, such as attempting to hold a stylus steady. In this examplemovement of the stylus such as involuntary shaking by the user orcharacteristics of the movement such as the user's shaking frequency aredefined as unintended motion and stored in motion profile 62. Inparticular embodiments, motion profiles 62 may be pre-set and stored ona stylus or device before the stylus or device is used by a user. Forexample, motion with acceleration greater than around 1 meter persecond² may be pre-defined as unintended. In particular embodiments, anymotion identified as unintended motion by motion profile 62 may bedynamically updated by a user, device, or stylus. For example, a stylusor device may edit or create a motion profile 62 by analyzing a set ofcharacteristics common or frequently appearing in one or more motionprofiles 62. A stylus or device may also edit or create a motion profile62 by analyzing user interaction with the stylus or device. For examplethe stylus or device may create a motion profile 62 relating to motionthat results in functionality a user consistently removes, such ascontent in a drawing program that a user consistently deletes. Whilethis disclosure provides specific examples of defining unintended motionby a user, stylus, or device in motion profiles 62, this disclosurecontemplates any suitable method of defining unintended motion of astylus, user, or device in motion profiles 62.

After the comparison in step 60, the one or more signals based on motionof the stylus or the device are processed in step 64 to correct forunintended motion defined by motion profiles 62. Processing may occur onsignals representing the stylus's motion, the device's motion, or both.In particular embodiments, a signal is processed by filtering from asignal one or more portions or characteristics of the signal defined asunintended motion. As an example, a stylus and device may undergorelative motion in a way the user does not intend, and this unintendedmotion results in signals the device processes as relative motion,leading to unintended functionality. One or more motion profiles 62identifies the signal (at any suitable stage before, during, or afterprocessing), or one or more of the signal's characteristics, created byunintended relative motion of the stylus and device. In particularembodiments, a motion profile 62 may indicate the device's motion isunintentional by combining the signals generated by unintended relativemotion with signals from an accelerometer in the stylus (or device)indicating lack of movement by the stylus (or device). The signalsgenerated by the unintended motion is then filtered by removing theportion of the signals representing unintended relative motion of thedevice as identified by motion profile 62, preventing unintendedfunctionality from occurring. The signals resulting from movementreturning the stylus or device to their relative positions prior to theunintended movement may also be filtered and removed. For example, auser may be using a stylus and device in a moving vehicle thatexperiences a sudden jolt. In this example, the stylus, the device, orboth could undergo unintended motion, for example by the stylus losingcontact with the touch-sensitive area of the device. Processing couldoccur on the unintended motion from the stylus, the device, or both tocorrect for the unintended motion. In addition, processing could occuron motion returning the stylus, the device, or both their intendedactual or relative positions prior to the jolt causing the unintendedmotion. This disclosure contemplates filtering signals representingmovement of a stylus or a device, or both. In addition, the signal (orits characteristics) stored by motion profiles 62 may occur at anysuitable time before, during, or after the signal is processed by thedevice or stylus.

In particular embodiments, processing of signals in step 64 may be usedto determine when or how to power one or more components on a stylus. Asan example, a stylus may have a variety of power modes defining howcomponents of the stylus are powered. Motion may be used to transitionthe stylus between two power modes. For example, shaking the stylus maytransition the stylus from a low-power “sleep” mode to a full-power “on”mode. Motion, such as travelling with the stylus, may unintentionallyreplicate the motion used to trigger transitions from one power mode toanother. If this motion is characterized as unintentional by one or moremotion profiles 62, then the portion of the motion identified asunintentional may be filtered, preventing the associated transitionbetween power modes. As another example, motion of a stylus may activatecomponents or initiate processes that consume power, such as thetransmission of high-voltage signals from electrodes in a stylus. If themotion that would activate components or initiate processes that consumepower is defined as unintentional by one or more motion profiles 62,then the unintentional motion is filtered, conserving power. While thisdisclosure describes particular examples of filtering specificunintended motions that trigger particular power-related functionality,this disclosure contemplates filtering any suitable unintended motionsthat trigger any suitable power-related functionality.

In particular embodiments, a signal is processed by adding content tothe signal. As an example, functionality associated with movements of astylus may require the stylus to be in a specific orientation orlocation with respect to the device. If the stylus or device movesunintentionally, the orientation or location of the stylus relative tothe device may be altered, preventing associated functionality fromoccurring. To correct for this when the device unintentionally moves,signals representing motion of the stylus may be processed by adding tothe signals content representing the unintended movement of the device,simulating the proper maintenance of orientation/location of the stylusand device. For example, if a stylus is on the left half of a device'sdisplay, and the device unintentionally moves to the left, this leftwardmovement may be added to the stylus' subsequent motion in order tomaintain relative stylus-device location prior to the unintended motion.In other words, signals generated by unintended relative motion of adevice may be added as an offset to subsequent signals generated byintended motion of the stylus in order to account for the unintendedmotion Likewise when the stylus unintentionally move, signalsrepresenting movement of the device may be processed by adding to thesignals a portion representing the unintended movement of the stylus.

In particular embodiments, a signal is processed by performing anysuitable operation on the signal, such as increasing or decreasing theamplitude of the signal or altering its component frequencies. Whilethis disclosure provides specific examples of filtering, adding to, oraltering signals representing motion of a stylus or a device to accountfor unintended motion, this disclosure contemplates any suitableprocessing of the signals to account for unintended motion.

Particular embodiments may repeat the steps of the method of FIG. 5,where appropriate. Moreover, although this disclosure describes andillustrates particular steps of the method of FIG. 5 as occurring in aparticular order, this disclosure contemplates any suitable steps of themethod of FIG. 5 occurring in any suitable order. Furthermore, althoughthis disclosure describes and illustrates particular components,devices, or systems carrying out particular steps of the method of FIG.5, this disclosure contemplates any suitable combination of any suitablecomponents, devices, or systems carrying out any suitable steps of themethod of FIG. 5.

Herein, reference to a computer-readable non-transitory storage mediumencompasses a semiconductor-based or other integrated circuit (IC)(such, as for example, a field-programmable gate array (FPGA) or anapplication-specific IC (ASIC)), a hard disk (HDD), a hybrid hard drive(HHD), an optical disc, an optical disc drive (ODD), a magneto-opticaldisc, a magneto-optical drive, a floppy disk, a floppy disk drive (FDD),magnetic tape, a holographic storage medium, a solid-state drive (SSD),a RAM-drive, a SECURE DIGITAL card, a SECURE DIGITAL drive, or anothersuitable computer-readable non-transitory storage medium or acombination of two or more of these, where appropriate. Acomputer-readable non-transitory storage medium may be volatile,non-volatile, or a combination of volatile and non-volatile, whereappropriate.

Herein, “or” is inclusive and not exclusive, unless expressly indicatedotherwise or indicated otherwise by context. Therefore, herein, “A or B”means “A, B, or both,” unless expressly indicated otherwise or indicatedotherwise by context. Moreover, “and” is both joint and several, unlessexpressly indicated otherwise or indicated otherwise by context.Therefore, herein, “A and B” means “A and B, jointly or severally,”unless expressly indicated otherwise or indicated otherwise by context.

This disclosure encompasses all changes, substitutions, variations,alterations, and modifications to the example embodiments herein that aperson having ordinary skill in the art would comprehend. Moreover,although this disclosure describes and illustrates respectiveembodiments herein as including particular components, elements,functions, operations, or steps, any of these embodiments may includeany combination or permutation of any of the components, elements,functions, operations, or steps described or illustrated anywhere hereinthat a person having ordinary skill in the art would comprehend.Furthermore, reference in the appended claims to an apparatus or systemor a component of an apparatus or system being adapted to, arranged to,capable of, configured to, enabled to, operable to, or operative toperform a particular function encompasses that apparatus, system,component, whether or not it or that particular function is activated,turned on, or unlocked, as long as that apparatus, system, or componentis so adapted, arranged, capable, configured, enabled, operable, oroperative.

The various embodiments described above can be combined to providefurther embodiments. All of the U.S. patents, U.S. patent applicationpublications, U.S. patent applications, foreign patents, foreign patentapplications and non-patent publications referred to in thisspecification and/or listed in the Application Data Sheet areincorporated herein by reference, in their entirety. Aspects of theembodiments can be modified, if necessary to employ concepts of thevarious patents, applications and publications to provide yet furtherembodiments.

These and other changes can be made to the embodiments in light of theabove-detailed description. In general, in the following claims, theterms used should not be construed to limit the claims to the specificembodiments disclosed in the specification and the claims, but should beconstrued to include all possible embodiments along with the full scopeof equivalents to which such claims are entitled. Accordingly, theclaims are not limited by the disclosure.

1. A stylus, comprising: a pen-tip; a sensor; and a processor operableto: operate in a lower-power mode and a higher-power mode; detect, withthe sensor, a defined frequency or a defined range of frequenciesindicating shaking of the stylus; transition from the lower-power modeto the higher-power mode in response to the detection of the definedfrequency or the defined range of frequencies; be prevented fromtransitioning from the lower-power mode to the higher-power mode inresponse to detection of a frequency other than the defined frequencyand of a range of frequencies other than the defined range offrequencies; and in response to a relative motion between the stylus anda device in communication with the stylus, process both a device signalrepresentative of the relative motion and a stylus signal representativeof the detection of the defined frequency or the defined range offrequencies.
 2. The stylus according to the claim 1, wherein thehigher-power mode is a mode in which a component for transmitting ahigh-voltage signal from an electrode in the stylus is activated, andthe lower power mode is a mode in which the component is deactivated. 3.The stylus according to claim 1, wherein the defined frequency or thedefined range of frequencies indicates unintentional shaking of thestylus as opposed to intentional shaking of the stylus.
 4. The stylusaccording to claim 1, wherein the processing of the device signalincludes adding a previous device signal representative of a previousrelative motion of the stylus with respect to the device as an offset tothe current device signal representative of the current relative motionof the stylus with respect to the device.
 5. The stylus according toclaim 4, wherein the previous relative motion of the stylus with respectto the device is a motion of the stylus in a first direction on adisplay of the device, and the previous device signal is added as theoffset to the current device signal.